Manufacture of halocarbons



Feb. 23, 1954 H. J. PAsslNo ET AL MANUFACTURE oF HALocARBoNs Filed NOV. 23, 1951 F l G HOO 900 IOOO RsAcTloN TEMPERATURE ,F

IO 2O 30 40 50 60 70 8O 90 IOO GOO 700 F l G. 2

INVEITORS HERBERT J. PASS INO WILBER O. TEETERS RUSSELL M. MANTELL VOLUME PERCENT CHLORINE IN FEED MIXTURE OF FLUORINE AND CHLORINE ATTORNEYS Patented Feb. 23, 1954 UN .l fre-o ,STATES es TENT fors icl-z "MANUFACTURE 0F HALOCRBONS Herbert .IQBassinmiEnglewnom rNVilherzG);Ileeters, :River Edge, :and Russell fMantell, frange, N.-..I.,fassignorsto.ThefM. Kellogg Company, J erscy City, TN. J., a corporation `of.Del:Lwarc AmlicationNovember 23, 1951,57Serial`fNoJ257W34 17-Claims. .l

'This :invention `relates to fan improved iprocess, :and'imore .particularly .pertains lto ani-improved .method .for produleing halocarbons. '-.Still :more particularly, :this invention :is yconcerned with improvements 1in .the A:manufacture of halecarbons by meansiofaa fluid system..

'The reaction of "iuorine with carbon in :the ipresence :of a halogen :other :than :iuorine tpro- A.duoes a mixture ofhalocarbonsaof various molecularWeights. Thepresencefofsarhalogen other t'han yiluorine, such Las for example, chlorine, .zapapears to favorably inuence the :rateof reaction .and 'makes possible 'a "bettereontrol Y.of vreaction 'conditions thanisfobtained when reacting fluor-ine :and carbon alone. Halocalfbons can tbe usedifor =a variety of purposes, particularly "those halo- Ycar`oons which contain :at least :5 `carbon fatoms Qin the .molecule Such `compounds fare usually referred to :as higher halocarbon products :and they can be used asadditives in lubricating oils, 4as-solvents, :as refrigerants, :extraction agents for :improving the quality of lubricating mils, transformer and dielectric oils, hydraulic '.luids, detc. There is an unlimited -use for halocalbons Aand lit `Tis important Ato provide methods vforproduc'ing same in substantial 4quantities and Vrfor thelowest cost. -rIfhe present invention is concerned"with providing van "improved 4process vfor producing 'halocarbons It Iis van object of the present invention to'proif :videanimproved-process for manufacturing halocarbone.

Another object of this invention is to `provide a 4fluid system `for producing halo'carbons.

:Still another object-'of this 'inventionisto proi" :vide A'an improved method rior `producing l'uorochlorocarbons.

ther objects and advantages of'thisinven'tion .metal :halide fand `a halogen 'other Lthan fluorin'e aand .fait :a .temperature of about v700" :to Sabot VIIOIYFF.

The lreaction .of ifluorine 'with carbon :in Ithe :presence fof 1an inorganic metal halide 'and 1.a

halogenlotherfthan uorineiis especially adapted .for aproducing hal'ocarbons, particularly/.fluorohalo'carhons. Therea'ction can=lbe carried iout-by employing :the carbon as a "lump, f pelleted, granular or finely divided'fmateria'l. '.Itfis/to-be noted, ihovvever, 'that a =system involving 'iluidizedi'car- :bonfis 'exceptionallybetterthan any oth'erimethod vforJeffecting lthe reaction. A fluid-'system aiords 'better .fcontrol :of Sthe temperature and more funi- :form reaction v:conditions `than iis :possible @with :other systems. l'The reaction ibetween carbon-and fuorine .is lhighly .fexothermid hence any system in #.vhich 'lth'e Jreactants become unevenly rr`dis- '.tributedfover 'fthe .reaction zone tends to develop fhot spots or 'regions 'rin the Areaction zone rhav- `fingunusuallysliightemperatures. Excessiveitemperatures "are to bez'avoided, because anyrprodu'ot materials subjected tosame ytend to decompose. Furthermore, any compounds Awhich may be'produced in the high 'temperature zones may differ from-what is sought, thus resulting in lower yields Sottndesiredf-product.

:To :attain a lflu'id system the carbon Hreactant vis .utilized in fa 'nel-y' divided state, generally 'having a particle-sizeof about A5 to f-a'bout 250imicrons, ".moreusually-.aboutlOto about `|100 microns. 'The i'carb'on 4:particles are iiuidized by Ypassing gaseous materials 4fupir/ardly through -a mass thereof, the yelocityof -which is-.suiiicientftosuspend the-partifcleszso `that Eitbe'haves asa pseudo-liquid. Generally, depending on 'the sizefof the carbon fparti- Vcles, .a .supercial linear -gas velocity fof yabout f0.1 to :50 ie'et per fsecond, more fusually about Oil to 6' zfeet .iper `second :is employed. The Ilarger fand more Adense particles requiring 'the 'higher ve- -locltiesand the oppositebeingtruefor the'smaller and less ldense particles. A linear gas tvelocity oi :the order mentioned'w'ill produce either a'llean or .dense phase. The lean lphase Ainvolves V`a lean concentration of particles.suspended'in'aJ gaseous material, thus ir'esu'lting Tin 'll'oW fluid densities.

0n the :other han-d, fthe idense phase 'or bed is a heavier concentration of suspended particles. For the present reaction, the dense phase is preferred because it provides a more intimate contact between the particles and the gaseous materials.

A uid bed is unusually adapted for the present invention because it provides more uniform temperatures and better control. The carbon particles in the huid bed are in random, circulatory motion. The particles move in every drection, thus resulting in a continuous circulation or mixing throughout the bed. As a result. there is a tendency :for uniform temperatures to exist in the bed. A fluid bed is also conducive to rapid restoration of equilibrium conditions, once the system has been upset or disturbed.

In some instances, it is preferred not to rely solely upon the reactant gas materials as the fiuidizing medium. An inert gas can be employed to supplement the gaseous reactant materials for producing the proper iiuidization of the carbon particles. The inert gas can serve a two-fold purpose, namely, of aiding in the uidization of the carbon particles and as a cooling medium. In some instances, the latter feature may be very important, hence, it would be desirable to employ an inert gas which contains a high specic heat, so that a small quantity can be used to effect the desired temperature control. The inert gases which are useful for this purpose can be any gaseous material which is substantially inert under the conditions of reaction. In this respect, generally the inert gases include helium, nitrogen, neon, etc. Generally, about 1 to 1000 cubic feet (measured at 60 F. and 760 mm.standard conditions), preferably about 10 to 100 standard cubic feet of inert gas per cubic foot of fluorine are employed.

The use of halogen other than iiuorine in the reaction has the apparent effect of reducing the velocity of reaction between fiucrine and carbon. This is a beneficial effect in view that the reaction between iiuorine and carbon takes place at a high rate accompanied by the liberation of large amounts of heat. It is also noted that the product contains mixed halocarbons. These mixed halocarbons can be used essentially for the same purpose as the fluorocarbons. For this invention ordinarily about to about 90%, pref.. erably about to about 60%, of fluorine based on the total volume of fluorine and a halogen other than uorine are employed. In such relative proportions, the reaction between iluorine and carbon takes place in a manner which readily lends to control. Although the halogen other than fluorine may be used in larger amounts than nuorine, the products produced usually contain more iiuorine than the other halogen.

In practicing our invention, the quantity of carbon employed is preferably in excess of the stoichiometric amount required to react with all of the uorine present. By maintaining the quantity of fiuorine at low concentrations relative to the amount of carbon, the reaction will proceed at a reasonably fast rate;` but at the same time, the iiuorine concentration is not suiilcient tocause the liberation of unusually large quantities of heat. Accordingly, for the purposes of this invention, about 0.001 to about 1.0 cubic foot (measured at 60 F. and 760 mm.) of iiuorine per minute per pound of carbon is generally used, preferably about 0.01 to 0.10 cubic foot of iluorine per minute per pound of carbon.

The halogen other than iiuorine which is used in the reaction can be, for example, chlorine,

bromine or iodine or mixtures of two or more of the foregoing. The halogen which is used, ordinarily will be found chemically combined in some or all of the compounds in the product, although in some cases the opposite is true. The volume per cent of fluorine in the halogen gas mixture is in the range of about 5 to about 65 in producing compounds containing at least 5 carbon atoms in the molecule. Quantities of uorine outside of this range result in little or negligible production of high boiling materials. This phenomenon will be discussed in more detail below, along with the data showing this characteristic of the reaction.

The improvements of the present invention are obtained by conducting the reaction in the presence of a catalyst which is an inorganic metal halide. The reaction of halogen with carbon is substantially improved with respect to yields of halocarbons when using the inorganic metal halide as catalyst. This catalytic material can be employed in quantities of about 0.1 to about 20%. The amount used generally depends upon the product distribution and yields desired. A concentration of at least about 8% by weight of the catalytic material, based on the carbon, provides higher yields of halocarbons than from the use of lower catalyst concentration. This effect may be obtained with catalyst concentrations of about 8 to about 12%, rbased on the weight of the carbon. Concentrations higher than 12% can be used, however. it is not preferred, because there is a tendency for the catalyst to deposit on the walls of the reaction vessel causing corrosion, etc. The inorganic metal halides include the fiuorides, chlorides, bromides and iodides of any metal. Examples of such catalytic materials are the halides of copper, silver and gold in group I, the halides of zinc, cadmium and mercury in group 1I, and the halides of iron, cobalt and nickel in group VIII. More specific illustrations of these catalysts are mercurio chloride, cobalt chloride, silver chloride, cupric chloride, zinc chloride, copper bromide, zinc bromide, mercurio bromide, mercurio iodide, etc.

The carbon reactant can be any material which furnishes carbon under reaction conditions and is substantially free of hydrogen. The absence of hydrogen is preferred, because under reaction conditions, there is a tendency for any free hydrogen to combine with the halogen and cause a reduction in product yield. Ordinarily, the carbon can be derived from such materials as charcoal, graphite, coke, etc. The charcoals appear to react more satisfactorily with halogen than any other carbon-yielding material. In this respect, the charcoal can be derived from wood, sugar, or any other suitable carboniferous material. Furthermore, any carbon-yielding material which contains elements or compounds other than carbon, may present problems in the recovery of desired halocarbons and for such a reason they should be avoided.

In the present invention, the temperature at which the reaction occurs may be selected on the basis of the type of material sought. Ordinarily, the reaction of fluorine with carbon in the presence of an inorganic metal halide and a halogen other than fluorine is conducted at a temperature of about 200 to about 1100 F. This temperature range includes the temperature at which halocarbons containing at least 5 carbon atoms in the molecule, and/or the low boiling halocarbons are formed. To derive halocarbons having at least 5 carbon atoms in the molecule,

accesso a temperature in the range of about 700 to, 1100 F. is used, otherwise, little orno yieldof such materials is obtained. At these temperatures, the reactant materials are present under a subwas supplied 'to the reactor by external lmeans through a 2500 watt electric jacket surrounding the same. Fluorine and inert gas were supplied to the bottom of the reactor by means of lines atmospheric, atmospheric or superatmospheric which were connected to suitable rotometers for pressure. Usually, a pressure in the range of measuring the gas rates. At the top of the reabout 0.5 to about atmospheres, preferably actor there was installed a suitable gauge for about 1 to about 3 atmospheres are used. measuring the reaction pressure. All of the ex- In order to provide a better understanding ci periments conducted in this apparatus are held the present invention, speciiic examples are 10 at atmospheric pressure. given below. However, it should be understood In Table I below, there is reported the results that no undue limitations or restrictions arefto obtained in determining the effect of temperabe imposed by reason thereof. ture on the yield of halocarbons containing at Experiments were conducted on a laboratory least 5 carbon atoms in the molecule.

Table I Yields, Wt. Percent (Output Basis) Example No. Chai-gel Temgfftm'e ClzrFnrNs Ellgrrgf b orgel. Gigi-ggg? leastcarbon atoms Norite-Hg-. 700 2: 1 ;4 30 Nil Nil ,do S00 2:1:4 .30 38 22 90o 2:1:4 .3o 22 is 1,000 2:1:4 .30 68 6 1,100 2:1;4 E30 75 3 voo 4:11a .i5 Nu N11 90o 4:1:8 .1 5 24 39 1 Norite-Hg is 50 grams of lill-T100 mesh Norite impregnated with 4 grams of HgCli.

scale in order to evaluate the conditions under which the reaction between carbon and uorine should be conducted. The apparatus employed for this purpose consisted of a monel reactor having a diameter of approximately l inch and being 36 inches long. A small settling chamber, 6 inches in length and approximately e inches in diameter, was superimposed on the reactor tube and contained a porous sintered monel iilter for the removal of entrained carbon particles from the effluent gaseous material. The illter was about 4 inches long and about 2 inches in diameter. lter and the reactor was a monel thermowell connected to the lower end of the lter by means of a sliding friction sleeve. This thermowell Was approximately 1A, in diameter and 34 inches in length. The thermowell contained a sliding iron-constantan thermocouple, 36 inches in length. Within kthe bottom of the reactor there was provided a support consisting of a pervious monel plate upon which there rested a monel tube having the outside diameter slightly smaller than the internal diameter of the reactor and having a length of 1 inch. This tube was iilled with a roll of 100 mesh nickel gauze. The nickel gauze permitted gases to pass through and distribute evenly over the cross-sectional area of the reactor. It also provides a means of supporting the carbon particles in thel reactor. Located on the support, there was a .1/2, x 4" monel sleeve in which the bottom end of the thermowell fitted. In this manner the thermowell was centered within the reactor. The filter, situated within the settling chamber, communicated with a Pyrex internal cold-finger liquid nitrogen trap having av 4 inch diameter and inch length by means of external connection. The liquid nitrogen trap was connected to a Pyrex, graduated, Podbielniak distillation kettle of mm. capacity. The kettle was maintained in a cooled condition by immersion in a Dewar iiask containing liquid nitrogen, Heat Concentrically disposed within the The data given in Table I is also plotted in Figure l of the attached drawings. It is to be noted that in order to produce noticeable quantities of halocarbons containing at least 5 carbon atoms in the molecule, it is necessary to employ a temperature of about 700 to about l F. Temperatures outside of this range result in the production of little or no halocarbons containing at least five carbon atoms. By means of Figure 1, the relationship between the temperature and the production of fluorochlorooarbons having at least ve carbon atoms in the molecule clearly demonstrates that the temperature is a critical factor in this reaction. Furthermore, it should be noted that in Example 6 of Table I, the increase in chlorine concentration ofthe reactant gases did not have any apparent beneficial effect on the reaction as long as the temperature remained at 700 F., which is outside of the critical range. This fact is borne out by Example 7 in the same table, wherein the conditions remained the same except that the temperature was raised to 900 F. By so doing, it was observed that substantial yields of halocarbons both of the low molecular weight and of the higher molecular weight are obtained.

Another interesting phenomenon is that the production of chlorotrifluoromethane is favored by temperatures greater than the optimum temperature for producing the halocarbons containing at least iive carbon atoms. In this regard', the light fiuorochlorocarbon is produced in substantial quantities at a temperature above 900 F. and reaches a maximum at a temperature of about 1l00 F. Hence, when it is desired to produce substantial quantities of triuorochloromethane, the reaction should be conducted at a temperature of about 900 lto about 1l00 F. A temperature lower than this range can be used as is evident from the test using a reaction temperature of 800 F., however, optimum producobtained, at a` temperature greater :than

s Additional experiments Were made to determine the eiect of the catalyst in the production .of halocarbons containing at least five carbon atoms in the molecule. These experiments are merely functioned 'as a .supplier of halogen. In View of the results obtained in Table II above, which show that the yield of iluorochlorocarbons containing at least carbon atoms increases subreported in Table II below. 5 stantially by the addition of mercurio chloride to Table II Flft. Peolent j Exemple Char Tempera- Flourine, omc 05' ge CILFLN; carbone o No. ture, F. Ft/Hr. carbon atoms (output basis) l Norite-Hg 1 900 2:1:4 .30 48 2 Norite L 900 2:1:4 .3U 28 l Norite-Hg is 50 grams of 40-100 mesh Norite impregnated with 4 grams HgCh.

I Norlte is 50 grams of 40-100 mesh wood charcoal.

It is shown in Table II that the use of a catalyst effects a substantial increase in the yield of halocarbons, particularly those containing at least ve carbon atoms in the molecule. It was observed that the reaction rate between carbon and luorine is favored by the presence of an inorganic metal halide to the extent that substantial yields of fluorocarbons are obtained and the reaction is susceptible to much better control. This eiect was believed to be due to the inorganic metal halide supplying halogen in a suitthe reaction involving uorine, chlorine and carbon, it now appears that the metal halide actually serves as a catalyst because the incremental increase in yield is not explainable on the basis that the metal halide furnishes halogen other than iiuorine, and hence, moderates the reaction. In Table III below, data is given which shows the results of employing various other materials as catalysts in the reaction of uorine and carbon in the presence of a halogen other than luorine.

Table III Yields, Wt. Percent Output Basis i Flourine Tempera- Example No. Charge 1 Cl2.FaN2 Etta/Hr. tures e F Fluonehlm 1 tocar ons one] 5 carbon atoms Noritc-CuClai.. 2:1:4 .30 900 68 9 Norlte-Co 013.- 2:1 :4 30 900 37 22 Nerim-211012.. 2:1:4 30 900 28 4l Norite-Hg TX2 2: l :4 30 900 42 23 1 5U grams of lill-100 mesh Norite impregnated with 4 grams of catalyst salt. 2 In this example, 8 grams of HgClz were used.

able form which causes the reaction between fluorine and carbon to slow down. As a result, itwas believed that the presence of a halogen other than uorine would have substantially the same magnitude of effect as the catalyst, if a comparable quantity of halogen were used in both instances. From the comparison in Table II, it can be seen that this is probably not the case, and quite unexpectedly, the use of a catalyst resulted in substantially improved yields. The efrect of the catalytic material on the yield of halocarbons is out of proportion to what is expected on the basis that the catalyst material merely serves to supply halogen in a suitable form in reducing the velocity of the reaction between carbon and iiuorine. In a copending application, S. N. 271,016, filed February l1, 1952, it is shown that the use of mercuric chloride as a catalyst results in the production of a iiuorochlorocarbon when reacting iluorine and carbon alone. The loss of 'chlorine in the catalytic material appears to indicate strongly that such a material is not a catalyst in the true sense, but that it may behave as a moderator of the reaction between lthe can bon and iiuorine. This phenomenon led some Workers to believe that the inorganic metal halide The data in Table III clearly demonstratesl that materials other than the mercury halides can be used as catalysts in producing halocarbons from the reaction'of fluorine with carbon in the presence of a halogen other than iiuorine. It is to be noted from the data in Tables II and III in columns 7 and 8, respectively, that the group II metal halides, viz., zinc chloride and mercurio chloride, employed in concentrations of 8% by weight based on the carbon produce exceptionally better yields of Yiluorochlorocarbons containing at least 5 carbon atoms than those instances in which the reaction is conducted without or With other types of catalysts including mercuryv cobalt chloride including mercurio chloride (16% by weight based on carbon) have a high selectivit;7 for producing triuorochloromethane.

The data reported in Table IV below, illustrates the effect of the 'relative proportions of 9 luorine and a halogen other than iluorine on the yields of halocarbons.

:l agrou'p VIII metal having an atomic number not greater than 28.

Table IV Yields, Wt. percent, Output Basis Exam 1e Nitrogen Flourine. Tempera- No.1 Charge CHF rtf/min. rta/hr. wenn. llllgr'g. 0F10] carbons, carbon y atoms 1 Norte-HgOh.-. 2:3 1.2 .30 900 64 10 2. .-.do 2:1 1.2 .30 900 '22 48 v 3-- 4:1 1.2 .15 900 24 39 4..-- 5:1 .90 900 60 13 1 50 grams of 40-100 mesh Norite (wood charcoal) impregnated with 4 grams of Hg'Clz,

The relationship between the yields of halocarbons containing at least 5 carbon atoms in the molecule and the percentage of fluorine in the total mixture of fluorine and a halogen other than uorine is plotted in Figure 2 of the attached drawings. This igure indicates that the yields of halocarbons containing at least 5 carbon atoms in the molecule are dependent upon the percentage of fluorine in the mixture of halogen gases. All of the experiments were conducted at a temperature of 900 F. which is shown by means of Table I to be the optimum temperature for producing the higher boiling halocarbons. Despite the use of this optimum temperature, it is noted from Figure 2 that the production of halocarbons having at least 5 carbon atoms in the molecule is dependent on certain percentages of iiuorine in the reactant gas mixture. On the basis of Figure 2 in order to produce perhalocarbons having at least 5 carbon atoms in the molecule in noticeable quantities, it is necessary to employ 5% to about 65% of fluorine, based on the total volume of the mixture of uorine and a halogen other than nuorine.

Having thus described my invention of giving specic illustrations thereof, it should be understood that the scope should be measured by the following claims.

We claim:

1. A process for preparing uorohalocarbons containing at least 5 carbon atoms whichcomprises introducing luorine and a halogen other than fluorine into a reaction zone in such amounts that uorine constitutes about 5 to about 65% by volume of the two halogens, reacting the halogens with carbon in the reaction zone at a temperature of about 700 to about 1100 F., and in the presence of not more than about 12 of a group II metal halide.

2. The process of claim 1 wherein the halogen other than uorine is chlorine.

3. The process of claim 1 wherein the halogen other than uorine is bromine.

4. A process for preparing triuorohalomethane which comprises introducing uorine and a halogen other than iluorine into a reaction zone, reacting the halogens with carbon in the reaction zone at a temperature of about 700 to about l100 F. and in the presence of a group IB metal halide.

5. A process for preparing triiluorohalomethane which comprises introducing iiuorine and a halogen other than fiuorine into a reaction zone, reacting the halogens with carbon in the reaction zone at a temperature of about 700 to about 1100 F. and in the presence of a halide of 6. YThe process of claim e wherein the halogen lother than uorine is chlorine.

'7. The process or" claim 5 wherein the halogen other than luorine is chlorine.

8. A process for preparing triucrohalomethane which comprises introducing a halogen other than fluorine and iluorine into a reaction zone, reacting the halogens with carbon Ain the reaction zone at a temperature of about 900 to about 1100-c7 F. and in the presence of a group IB metal halide.

9. A process for preparing triiiuorohaiomethane which comprises introducing a halogen other than iiuorine and fluorine into a reaction zone, reacting the halogens with carbon in the reaction rone at a temperature of about 900 to about 1i00 F. and in the presence of a halide of a group VIII metal having an atomic number not greater than 28.

10. A process for preparing fluorehalocarbons containing at least 5 carbon atoms which comprises introducing uorine and a halogen other than fiuorine into a reaction zone in v such amounts that uorine constitutes about 5 to about 60% by volume of the two halogens, react ing the halogens with carbon in the reaction zone at a temperature of about 700 to about 1100 F. and in the presence of about 8 to about 12% of a group II metal chloride.

11. The process oi claim 10 wherein the halon gen other than iluorine is chlorine and the group II metal chloride is mercuric chloride.

12. The process of claim 10 wherein the halogen other than iiuorine is chlorine and the group II metal chloride is zinc chloride.

13. A process for preparing iiuorochlorocarbons containing at least 5 carbon atoms which comprises introducing chlorine and iluorine into a reaction zone in such amounts that the iiuorine constitutes about 33% by volume of the two halogens, reacting the two halogens with carbon in the reaction zone at a temperature of about 900 F. and in the presence of about 8% of mercuric chloride.

14. A process for producing halocarbons which comprises introducing luorine and a halogen other than iluorine into a reaction zone, and reacting the halogens with carbon in the presence of'a metal halide.

15. A process for producing halocarbons which comprises introducing iluorine and a halogen other than iluorine into a reaction zone, reacting the halogens with carbon in the reaction zone at a temperature of about 200 to about 1100* F., and in the presence of a metal halide.

16. A process for producing halocarbons which comprises introducing uorine and a halogen 11 other than uorine into a reaction zone in'such amounts that fluorine constitutes about 5 to about 90% by volume of the two halogens, reacting the halogens with carbon in the reaction zone at a temperature of about 200 to about 1100 F., and in the presence of a metal halide.

17. A process for producing haiocarbons which comprises introducing uorine and a halogen other than fluorine into a reaction zone in such amounts that fluorine constitutes about 5 to about 90% by volume of the two halogens, reacting the halogens with carbon inthe reaction zone at a. temperature of about 700 to about 1100 F., and in the presence of about 0.1 to about 20% of a metal halide.

HERBERT J. FASSINO, WILBER, 0. TEETERS. RUSSELL M. MANTELL.

Name Date Simons Dec. 14, 1948 OTHER REFERENCES Simons et al.: J. A. C. S. 61, pp. 2962-56 (1939). McBee et a1.: Oil and Gas J. 46, p. 59 (1947).

Number 

14. A PROCESS FOR PRODUCING HALOCARBONS WHICH COMPRISES INTRODUCING FLUORINE AND A HALOGEN OTHER THAN FLUORINE INTO A REACTION ZONE, AND RACTING THE HALOGENS WITH CARBON IN THE PRESENCE OF A METAL HALIDE. 